Polyethylene film-forming composition



coosr om Witty 1L. Alclerson, 312, W i

or to E. E. in Pent do Nemonrs & Qom any,

mill, Del... o oorcorstion of. Delaware collection senate, toss,

This invention relates to new compositions of matter and to methods for their preparation.

The invention has as an object the preparation s (cl; toil-=23) of new and improved film-forming compositions.

A further object is the production of valuable supported and unsupported films. Uther objects are disclosed hereinafter.

The above objects are accomplished by blendinc in the manner more particularly pointed out hereinafter e. normally solici poly er or ethylene and a mixture of a naturelh occurring fatty acid glycericle and an ester of a cerhoxylicacici containing at least 1 carbon atoms with an alcohol containing at least 8 carbon atoms one. preferably 11-18 carbon atoms.

in the best method oi practicing the invention the normally solid ethylene honor is blended. usually by milling on rolls, with the fatty acid glrcericle and an ester of s carhox ylic acid con taimne at least it carbon stems with on alcohol 2 positions can he obtained however with esters o alcohols containing eight or more carbon atoms. Examples of other esters that can replace that used in the foregoing example comprise ciodecyl stearate, myricyl linoleate, octedecaneciiol monolaurate, octyl arachidate, uecyl eicosanate, lauryl psl'mitete and. the like. l'he proportions of the ethylene polymer to the mixture of ester and glyceride and of the ester and glyceride in the mixture thereof can vary somewhat from that given in the best emhotii merit of the invention outlined alcove. Generally the mixture of glycericle enci ester constitutes from il.l% to by weight of the ethylene ooh:-

contsg ii to it cartoon atoms, the ore of 7 fatty sold slyceritle and, ester constituting-from 6.5% to 2% by weight oi the ethylene polymer and the mixture of clyceride e ester consisting oi from to t0% oi the c yceride anti fire to 6M2 oi the ester.

The iollowing example, in which the ports ore by weight. further illustrates the practice of the invention. I

into its ports of a'polymer of ethylene herring a molecular weight oi shout 15,009 is worked one part oi undecyl stecrate and 0.5 port of p oil icy milling on rolls hosted at rec-1st" C. The hot 7 the middle and bottom rolls of the celender the composition is stripped from the hotto oi the lowest roll in the form of acontinuous :r i it with the aid of an air blast directed es the surfsce oi the calender roll at the point where the is stripped. The film thus obtained is tough, flexible and essentially tree from pin-holes. It is well adapted for use as e moisture prooi wrao= ping foil. t

Replacement of the pslrn oil in the above com-- position with other naturally occur" 1 fatty acid slycerides, such es, coconut oiLlinseed oil, etc, elves products oi m. 5 properties.

The long chain ester of the carboxylic acid contsinins at least is carbon stoma is, as previously indicated creed preferably with on alcohol con ii to it cocoon cross mer and. wherein theminture oi glyceride end ester consists of from 10% to 50% of the elyceriole and from to 50% of the ester.

The temperature oi the calender rolls is criticsl for the successful production oi well=iormee s. In general, the rolls should be maintained icetween end 150 0., if touch films which are free of holes are to be obtained. If temperatures in excess of 150 C. are used, the is too soft and below 110 C. it is not suficieutly plastic ior removal from" the rolls as a continuous, touch. As a rule, it is prererreri to retain the rolls between oml C. In order to re temoturos, corrcsoonrl in com more hires having a thickness of less than t v; s, it is necessary to resort to the use of an sir hit es described in the example. Thicker #12:" say from loss rolls in thickness can he removed iro the rolls without the use of an air hlest. One of the important advantages of thin illms is that they are smoother, more pliable and. more tronsperent than thick films and hence more readily adaptable for use as wrappins foils, and for cost ing fabrics. lore constitutes a particular, preferred embodiemerit of this invention.

The solid. ethylene polymers whichare usedir. the practice oi this invention are made by heating ethylene alone, as described in U. S. Patents 2,153,553 and 2,168,465 or in nture with one other poerizahle organic compound, as descriloed in U. 8. Patent 2,200,429. The polymers of ethylene clone or in 231 ture with other po erizable organic compounds can also 1 he. obtained by contacting ethylene clone or in somiiztnre with another polymericahle-orgemc compound with water and a screw compound at a temperature in the range of t0-35 C. and under a pressure in excess of ao'sp heric, end preterahly in the range or s-icco atmospheres. "lihe polymers oi ethylene alone are solids at not 1 The production oi such films there-- ethylene with other polymerizable organic compounds depend upon the composition of the polymer and the nature of the polymerizable organic compound.

- The compositions described herein make possible the preparation from ethylene polymer of valuable unsupported transparent films, and particularly of thin films of'enhanced utility. These compositions are also useful in the preparation of improved supported films by calenderirig on a to be understood that I do not lumtm sirto the specific embodiments thereof, except as defined in the appended claims.

I claim! V a 1. A composition of matter comprising in maior amounte, normally solid polymer of ethylene and a mixture in amount of ;i.'rom 0.1% to 10% by weight of said polymer. of naturally occurring fatty acid glyceride and an ester of a carboxylic acid containing at least 14 carbon atoms with an alcohol containing at least 8 carbon atoms,

non-rigid support, such as paper, fabric or metal foil.

The compositions described herein, as compared to known ethylene polymer compositions, are of special value in that they can be readily sheeted on calender rolls at temperaturesabove 120 C. into tough, transparent and flexible films. This is an important characteristic because optimum film properties cannot be realized in the prior manufacture oi ethylene polymer films at temperatures below about 125 C. by calendering technique which has'many recognized advandeparting from the; spirit and scope thereof, it-is said mixture consisting of from 10% to of said glyceride and from 90% to 50% of said ester. 2. A self supported film comprising the com position set forth in claim 1.v

3. A flexible base material coated with a film of the composition set forth in claim 1 1 4. The composition set forth in claim 1 in which said mixzture is present in amount of from 0.5% to 2% by weight of said ethylene polymer and in which said mixture consists of from 25% to 40% of said glyceride and from to 60% of said ester.

5. A composition of matter comprising in major amount a normally solid polymer of ethylene and a mixture, in amount of from 0.1% to 10% by weight of said polymer, of palmoil and undecyl stearate. said mixture consisting of from 10% to 50% of the palmoil and from to 50% of the 30 undecyl stearate.

WITI'Y L. ALDERSON, JR. 

